KO Reader

KO Reader turns web articles, ebooks, and PDFs into natural-sounding speech — entirely on your device. No cloud, no tracking, no subscriptions.
Paste a URL or open an EPUB or PDF, and KO Reader reads it aloud with a neural AI voice. Everything runs locally, so your reading stays private and works anywhere — on the train, on a plane, or off-grid. Export your favorite articles or books to m4a or m4b files.

WHAT YOU CAN READ

• Web articles — Wikipedia, news sites, blogs, and Substack
• Fanfiction — Archive of Our Own, Royal Road, and Wattpad, with chapter detection
• EPUB ebooks with full chapter navigation
• PDF documents
• Plain text — paste or type any content
• Safari Share Extension — send articles to KO Reader with one tap

NATURAL AI VOICES

• 53 neural voices across 9 languages: American and British English, Spanish, French, Italian, Portuguese, Japanese, Mandarin, and Hindi
• Preview any voice before selecting it
• Mark favorites for quick access
• Playback speed from 0.5x to 2.0x
• Smart heteronym resolution — the voice knows the difference between "lead" (the metal) and "lead" (to guide), "wound" (injury) and "wound" (past of wind)
• Custom pronunciation dictionary — teach the reader how to say names, jargon, or anything you like

READ YOUR WAY

• Reading queue — line up multiple articles and auto-advance
• Bookmarks — save passages to come back to
• Reading history — pick up where you left off, across books and articles
• Chapter pre-generation — book chapters start instantly, no waiting between them
• Audio export — save generated audio for offline listening
• Adjustable article font (system, serif, monospaced, rounded) and Dynamic Type support

BUILT FOR ACCESSIBILITY

• Full VoiceOver support with labeled controls throughout
• Haptic feedback on transport controls and sleep timer
• Background audio — listen while you use other apps or with the screen off
• Sleep timer — stops playback when you drift off
• Works with AirPods, Bluetooth speakers, and CarPlay

RUNS EVERYWHERE

• Universal app for iPhone, iPad, and Mac
• macOS keyboard shortcuts (Space to play/pause, Cmd+← and Cmd+→ to skip)
• Optimized for Apple Silicon with optional CoreML acceleration
• Adjustable CPU thread count for performance tuning

PRIVACY FIRST

• 100% on-device TTS — your content never leaves your phone
• No accounts, no analytics, no tracking, no ads
• No internet required after the one-time model download
• Reading progress stored locally only

KO Reader downloads a ~350 MB neural voice model on first launch. After that, everything works fully offline.

Powered by the open-source Kokoro TTS model (Apache 2.0).